Wireless streaming video transport is challenging. The error-prone nature of wireless networks usually causes channel congestion, which results in a serious loss of signal packets, especially when motion is involved.
Video signals require very high bandwidth if they are transmitted in raw form. To save on bandwidth, video signals are often compressed into variable bit-rate (VBR) output stream containing control information (e.g., frame headers) whose loss could lead to misinterpretation or discarding of a large portion of otherwise correctly received data, thus resulting in a significant drop in visual quality.
Wireless streaming video communication is particularly challenging because it combines the already difficult problem of efficient compression with the additional and usually contradictory need to make the compressed bit stream robust to channel errors.
A good error resilient application system is Quality of Service (QoS) adaptive. QoS may be used to describe the overall performance of a communication system. To be QoS adaptive is to trade off different QoS requirements. For wireless video applications, QoS may be measured by the reliability, latency, and bandwidth usage, which are in terms of Peak Signal to Noise Ratio (PSNR), Packet Loss Rate (PLR), Delay, Delay Variation/Jitter, and Bit Throughput Rate (BTR).
There is no clear mathematical model that can be used when channel congestion happens, the QoS requirements are often too conflicting to compromise, and the endeavors to make application systems robust are significantly complicated. Protocol may depend on the tradeoff between performance gain and acceptable cost/complexity. Techniques for error resilience may be classified as: 1) source level; 2) channel level; 3) receiver level; or 4) system level.
Limitations and disadvantages of conventional and traditional approaches will become apparent to one of ordinary skill in the art through comparison of such systems with the present invention as set forth in the remainder of the present application with reference to the drawings.